1. Field of the Invention
This invention relates to quaternary ammonium group-containing polymers. More particularly it concerns a family of such polymers that exhibit antimicrobial activity and their application as antimicrobials.
2. Prior Art
Quaternary ammonium group-containing polymers have been widely studied. A review of the literature has turned up a vast collection of references to the general subject. As this invention relates to quaternary ammonium polymeric compounds having antimicrobial activity as well as to certain new copolymeric quaternary polymers, three references to Green et al may be of interest. These references, U.S. Pat. Nos. 3,931,319; 4,005,193; and 4,025,617, disclose polymeric quaternary ammonium polymers having antimicrobial activity. However, Green et al's polymers are structurally dissimilar to the present materials.
The polymers of the invention may be classified as having a poly(vinylbenzyl quaternary ammonium)halide structure. In certain embodiments, they have a copolymer structure with repeating ##STR1## X.sup.- =physiologically acceptable anion R's=alkyls
q=1 to 4, preferably 2 PA0 a. polymerizing vinylbenzyl halide plus any optional comonomer units using free-radical catalysis, and PA0 b. reacting the resulting poly(vinylbenzyl halide) with tertiary amine to yield the desired quaternary amine which is thereafter recovered.
units.
U.S. Pat. Nos. 2,702,795 of Gilwood; 2,772,310 of Morris; 3,563,949 of Hartenstein and 4,087,599 of Roe et al, as well as Journal of Polymer Science, Polymer Chemistry Edition, Vol. 18, pp. 455-65, 619-80, Dragan et al, are certainly of interest as they show similar groups but do not suggest the present materials.
These polymeric quaternary compounds fill a well identified and recognized need for a polymeric antimicrobial agent similar to or surpassing known nonpolymeric species such as hexachlorophene, Zephiran.RTM. and the like. Being large polymeric molecules, the present materials are less mobile and less likely to migrate or inappropriately penetrate or be absorbed into substrates. This permits their use in environments where penetration or displacement or volatilization are problems. Further, it permits residual antimicrobial activity to be imparted to surfaces and the like by the use of these materials.